This paper presents results of an experimental investigation solute transport in a simplified model the spinal canal. The work aims to provide increased understanding mechanisms responsible for drug dispersion intrathecal delivery (ITDD) procedures. consists annular channel bounded externally by rigid transparent tube circular section, representing dura mater, and internally eccentric cylindric...

In this paper peristaltic transport of a power law fluid in an asymmetric channel bounded by permeable beds is studied under long wavelength and low Reynolds number assumptions. The channel asymmetry is produced by choosing the peristaltic wave train on the walls to have different amplitude and phase due to the variation of channel width, wave amplitudes and phase differences. Expressions for t...

Intestinal segments obtained from guinea pig ileum were set up in an organ bath to record peristaltic responses to distension by a pressure rise in the lumen. The effects of drugs applied in the bathing medium on the peristaltic responses were examined. Sodium nitroprusside (10(-9) M to 10(-5) M) stimulated the peristaltic reflex. Nitroglycerin (10(-7) M) was similarly effective in stimulating ...

The peristaltic reflex can be evoked in the absence of input from the CNS because the responsible neural pathways are intrinsic to the intestine. Mucosal enterochromaffin cells have been postulated to be pressure transducers, which activate the intrinsic sensory neurons that initiate the reflex by secreting 5-HT. All of the criteria necessary to establish 5-HT as this transmitter have been fulf...

Gastric peristaltic contractions are controlled by an intrinsic electrical pacemaker located in the mid-body along the greater curve. This study was undertaken to investigate gastric motility in long-term survivors of neonatal gastric rupture who were surgically deprived of their original pacemaker. Four patients, 1 boy and 3 girls, aged between 6 and 12 years were studied. Physiological activi...

The design of a novel, microfluidic chip with an integrated micro peristaltic pump and chambers for DNA amplification is described. This chip contains three reaction chambers stable at 90 ◦C, 72 ◦C and 55 ◦C for PCR amplification, a bi-directional peristaltic pump and optical integrated detection of the droplet. A reactant droplet is to be introduced into the device, pumped back and forth betwe...

BACKGROUND Esophageal motility abnormalities include a series of manometric findings that differ to a significant degree from findings in normal, asymptomatic volunteers. METHODS Current review summarizes conventional and high-resolution esophageal manometry criteria used to define and characterize esophageal hypertensive motility abnormalities. KEY RESULTS In the conventional esophageal ma...

The peristaltic flow of a Jeffrey fluid with variable viscosity through a porous medium in an asymmetric channel is investigated. The channel asymmetric is produced by choosing the peristaltic wave train on thewall of different amplitude and phase. The governing nonlinear partial differential equations for the Jeffrey fluid model are derived in Cartesian coordinates system. Analytic solutions f...

Slip effects on the peristaltic transport of Johnson-Segalman fluid through a curved channel have been addressed. The influence of wall properties is also analyzed. Long wavelength and low Reynolds number assumptions have been utilized in the mathematical formulation of the problem. The equations so formed have been solved numerically by shooting method through computational software Mathematic...

This paper is devoted to the study of the two-dimensional flow of a Johnson-Segalman fluid in a planar channel having walls that are transversely displaced by an infinite, harmonic travelling wave of large wavelength. Both analytical and numerical solutions are presented. The analysis for the analytical solution is carried out for small Weissenberg numbers. (A Weissenberg number is the ratio of...